Oh my goodness, what a thing of beauty and a joy for ever. Watch out for oil leakage on that Sprague cap (its "Clorinol" name suggests polychlorinated biphenyl oil inside) and check out the wires to see if it was not a Fluke... erm, to see if their insulation is not made of asbestos. Sometimes old electronics is full of hazardous materials :(.
Nice! I haven't seen anything on youtube (or elsewhere on the internet) about these yet but then again I haven't exactly been looking for details about them. I happen to have the 4kV version (I think) and I'm not sure what I can use it for. I think its current output is even less - much less than 30mA - but I can't be sure right now. For a time I was considering of using it as a power supply for electrostatics but there is really no point (that would be tantamount to the definition of overkill squared or perhaps cubed). Learning here that these were primarily intended for lab use - well, kind of obvious really but then one can never know a priori - kind of clear things up a bit. 2:33 6080 tubes are available as NOS still and their sisters, 6AS7 tubes were still made by Sovtek/Svetlana at least until recently - not sure what the situation is now. You do need two of them so the price seems right, if not a little bit low. 6:53 Ha! Understatement or what?
very nice power supply and teardown. 8068 looks very similar to a 6BG6 but with much higher power and voltage. possible replacement would be tube color TV Line output tube
Awesome video, thanks for posting - you seem to be the sole source of information 412B! I've got one of these open on my bench right now that I've had for a few years and just got around to troubleshooting. The HV supply and regulation work perfectly, but only if I manually close that open frame power relay. I'm pretty sure the time delay relay tube (or its control circuitry) is bad, BUT the part number is illegible so I'm kind of stuck. After I close the main HV relay, both of them operate normally from the HV switch on the front panel, so I think that localizes it to the time delay circuit. Any chance you have a schematic you'd be willing to share, or at least a part number for that time delay tube? Any info would be appreciated. Thanks!
Ah, that time delay relay was easier to find than I'd suspected - Amperite 115N030 - even found a datasheet. No luck on a schematic or service manual, though
Sorry for the late reply... I looked for a manual for years, even bought what I thought was it from NASA JPL auction... It was for the 412B that is not adjustable... My assumption is there is no longer a surviving schematic. That being said the regulation system appears to be identical to other 400 series like the 410 or 415, and you can find the manuals online. The reference designation will be different, but using the pictures in the manual you can transcribe. See my HackaDay project for more schematic info.
Thank you for this video. Got a 412B here that apparently needs some calibration. First dial on 1000V, all other on 0 yields 706V. Second dial on 100, all other on 0 yields 70V. So there seems to a a constant factor of 0.7. Any hint on how to calibrate the supply? Can't seem to find a complete manual online.
@@TheMadHatter1337Hi. You are right about the calibration pot. I can adjust about 5 volts. Any hints on how to locate the resistor? I assume it is located in the right third?
I would check the same resistor i show in the video, i think my supply had a similar issue to yours with a 2/3v output from expected. If you are not comfortable working around high voltage, you may want to find someone who is. The voltages on the right sode regulation board should be within 200v of the set point, so a low set-point makes it a bit less dangerous
I just got one of these off Ebay byt what output cables are you supposed to use with these? I can't find any BNC cable anywhere near rated for 2kV...at least from reputable suppliers.
@@DKNguyen3.1415 it depends... Mine had a bnc on the front and a higher voltage one on back... I assume people swapped them out often. That being said, coax bnc when made well can typically handle a few KV. The voltage ratings are often not advertised.
This is so cool! I had no idea these supplies were so interesting inside
Oh my goodness, what a thing of beauty and a joy for ever. Watch out for oil leakage on that Sprague cap (its "Clorinol" name suggests polychlorinated biphenyl oil inside) and check out the wires to see if it was not a Fluke... erm, to see if their insulation is not made of asbestos. Sometimes old electronics is full of hazardous materials :(.
Nice! I haven't seen anything on youtube (or elsewhere on the internet) about these yet but then again I haven't exactly been looking for details about them. I happen to have the 4kV version (I think) and I'm not sure what I can use it for. I think its current output is even less - much less than 30mA - but I can't be sure right now. For a time I was considering of using it as a power supply for electrostatics but there is really no point (that would be tantamount to the definition of overkill squared or perhaps cubed). Learning here that these were primarily intended for lab use - well, kind of obvious really but then one can never know a priori - kind of clear things up a bit.
2:33 6080 tubes are available as NOS still and their sisters, 6AS7 tubes were still made by Sovtek/Svetlana at least until recently - not sure what the situation is now. You do need two of them so the price seems right, if not a little bit low.
6:53 Ha! Understatement or what?
very nice power supply and teardown. 8068 looks very similar to a 6BG6 but with much higher power and voltage. possible replacement would be tube color TV Line output tube
Cool
Awesome video, thanks for posting - you seem to be the sole source of information 412B!
I've got one of these open on my bench right now that I've had for a few years and just got around to troubleshooting. The HV supply and regulation work perfectly, but only if I manually close that open frame power relay. I'm pretty sure the time delay relay tube (or its control circuitry) is bad, BUT the part number is illegible so I'm kind of stuck. After I close the main HV relay, both of them operate normally from the HV switch on the front panel, so I think that localizes it to the time delay circuit.
Any chance you have a schematic you'd be willing to share, or at least a part number for that time delay tube? Any info would be appreciated. Thanks!
Ah, that time delay relay was easier to find than I'd suspected - Amperite 115N030 - even found a datasheet. No luck on a schematic or service manual, though
Sorry for the late reply... I looked for a manual for years, even bought what I thought was it from NASA JPL auction... It was for the 412B that is not adjustable... My assumption is there is no longer a surviving schematic. That being said the regulation system appears to be identical to other 400 series like the 410 or 415, and you can find the manuals online. The reference designation will be different, but using the pictures in the manual you can transcribe. See my HackaDay project for more schematic info.
Thank you for this video. Got a 412B here that apparently needs some calibration. First dial on 1000V, all other on 0 yields 706V. Second dial on 100, all other on 0 yields 70V. So there seems to a a constant factor of 0.7. Any hint on how to calibrate the supply? Can't seem to find a complete manual online.
Sounds similar to my issue… most likely a bad resistor. The calibration pot only adjusts by a few volts.
@@TheMadHatter1337Hi. You are right about the calibration pot. I can adjust about 5 volts. Any hints on how to locate the resistor? I assume it is located in the right third?
I would check the same resistor i show in the video, i think my supply had a similar issue to yours with a 2/3v output from expected. If you are not comfortable working around high voltage, you may want to find someone who is. The voltages on the right sode regulation board should be within 200v of the set point, so a low set-point makes it a bit less dangerous
@@TheMadHatter1337Will do. Thank you!
@@TheMadHatter1337 Thank you for your advice. I measured the resistor (in circuit) and it is 3,5kR :/
I just got one of these off Ebay byt what output cables are you supposed to use with these? I can't find any BNC cable anywhere near rated for 2kV...at least from reputable suppliers.
Looking around it seems what I need are actually MHV or SHV cables, not BNC?
@@DKNguyen3.1415 it depends... Mine had a bnc on the front and a higher voltage one on back... I assume people swapped them out often. That being said, coax bnc when made well can typically handle a few KV. The voltage ratings are often not advertised.